Somatostatin inhibition of teleost growth hormone secretion

Abstract

Pituitary glands of a teleost, tilapia (Sarotherodon mossambicus), were incubated in vitro in the presence or absence of synthetic somatostatin. After a 4-hr incubation period, the growth hormone (GH) concentration of the incubation medium was determined using a highly specific homologous radioreceptor assay. The presence of somatostatin in the incubation medium at concentrations of 0.1 to 2.0 μg/ml produced a dose-dependent inhibition of the spontaneous release of GH. These results suggest that GH secretion in teleosts may be influenced by a somatostatin-like peptide which acts to suppress the release of GH from the pituitary.